Loading skip



`lune 20, 1933. A W RYBECK 1,914,385

LOADING SKIP Filed OCC. l2, 1928 Patented June 20, 1933 UNITED STATESPATENT OFFICE ADOLPH W. RYBECK, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO T.L. SMITH COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION F WISCONSINLOADING SKIP Application led October 12, 1928.

This invention relates to certain new and useful improvements in skiphoists and refers more particularly to skips of the type especially usedwith concrete miXers,'paving machines and the like.

In skips of this nature, and particularly where they are used inconnection with large paving machines and the like, the load isappreciable and places excessive strains on its hoisting' elements,especially during the initial raising of the skip at which time theinertia is greatest and the degree of 'leverage is at its minimum, andtherefore this invention has as an object the provision of means forincreasing the lifting power of the hoist at the time of initial raisingof the skip.

Another' object of this invention resides in the provision of means forincreasing the eective lifting force of the hoisting mechanism of adevice of the character described which is so designed as to require buta relatively minorkchange yin the usual construction of such hoistingmechanisms.

This invention has as another object the provision of means forincreasing the lifting power of a hoisting mechanism for skips of thecharacter described which also obviates the usual spring shock absorbingmeans heretofore employed to cushion the shock incidental to the skipreaching its load receiving position.

A further object of this invention resides in the provision of a sheavepositioned upwardly of the sheaves carried by the skip and about whichthe hoisting cable passes, to reduce the load on the hoisting elementsat the time of initial upward movement.

And a still further object of this invention resides in the provision ofmeansfor increasing the lifting force of a hoisting mechanism of thecharacter described which automatically becomes ineffective after apredetermined movement of the skip whereby maximum lifting force isobtained with a.

minimum loss of time.

Serial No. 312,063.

IVith the above and other objects in view which will appear as thedescription proceeds, my invention resides in the no-vel construction,combination and arrangement of parts substantially as hereinafterdescribed and more particularly defined by the appended claims, it beingunderstood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

In the accompanying drawing, I have illustrated one complete example ofthe physical embodiment of my invention constructed according to thebest mode I have so far devised for the practical application of theprinciples thereof, and in which:

Figure 1 is a side elevational view of a portion of a machineillustrating my invention as applied thereto;

Figure 2 is a View taken on the of the line 2 2 of Figure l, and

Figure 3 is a detail view of the sheave block detached from the skip.

Referring now more particularly to the accompanying drawing, in whichlike numerals designate like parts, 5 represents the base of a pavingmachine, concrete mixer or the like from which frame members 6 extendupwardly to support the various instrumentalities of the machine. Gussetplates 7 connect adjacent frame members 6 and provide a pivotal support8 for the mounting arm 9 of a skip l0, consisting of the `usual loadreceiving body or portion ll and a discharge chute l2, the mounting armthereof lbeing riveted or otherwise secured to the skip adjacent chutel2.

As is customary in devices of this nature, the skip is adapted to bemoved from its plane dotted lines discharging its load into the mixingdrum 13 of the machine, movement of the skip is effected through themedium of a hoisting cable 14, the ends of which load receiving positionillustrated in full .85

Vlines in Figure l to a position shown in are connected with drums 15fixed on the ends of a shaft 16 mounted in suitable bearings, not shown,carried by the frame and carrying a drive pulley 17. A cable 1S havingone end connected with the pulley 17 is wound thereon and has its otherend fixed to a drum 19 on which it is wound when it is desired to raisethe skip. The drum 19 receives its drive from a shaft 19 connect-ed withthe machine power plant, not shown, and adapted to provide the drive forthedrum 13.

Heretof'ore, the medial portion of' cable 14 passed over a pair ofsheaves 2() mounted between supporting `members 21 pivota-lly" connectedwith the skip proper by straps 22, a pivot rod 23 and supporting members24, so that as the ends of' the cable were wound on their respectivedrums 15, the skip was elevated.

It lwill bereadily apparent that excessive strains are placed on thehoisting elements of'- the machine atthe time of initial raising.

of the skip, as the leverage is at a minimum point, and to reduce theload the present invention contemplates the use of an additional sheave25 carried by a sheave block 26 and over which that stretch 'ofthe-cable 14 between the sheaves 2O passes. The

sheave block 26 is further provided with a pulley 27 at its inner endabout which a cable or chain 28 is trained, the ends of which aresecured to anchoring members 29 connected with the upper portion of theframe members 6 to support the sheave block 26 andconsequentlythe'sheave 25 in a position upwardly of' the sheaves 20.Thus it will be seen that a substantial percentage,I

of the load is carried by the chain 28 and that the hoisting mechanismis materially relieved of the stresses imposed-atthe time of initialraising.

The point at which the sheave 25 is posi'- tionedy governs the durationof time during which it is effective, for as the skip moves upward, thedistance between the sheave 25 and the sheaves 20 decreases to a point(shown in dotted lines in Figure 2)4 at which the sheave 25 is in linewith the sheaves 20' when the pull is directl on'the sheaves 20. Fromvthis Apoint to thegc ischarging position, the chain 28 is slack'and theblock, 26 is positioned between thev members 2l where it remains untilthe skip, in its downward movement, again reaches this point. As theskip is lowered, the sheave 25 gradually becomes effective and thusactsas a shock' absorbing means to ease orjcushion thevreturn'of the skip toits load receiving position.

From the foregoing description taken `in connection with theaccompanying drawing,

it will be readily apparentto those skilled in the art to which aninventionl of the character described. appertains, thatI pro-y videnovel means for reducing the strain on the hoisting mechanism for skipsat the time of greatest inertia, which does not materially reduce thespeed of operation and which cushions the return of the skip.

What I claim as my invention is:

1. In combination with a loading skip adapted to be raised and lowered,cable means for raising the skip, and substantially fixed means aboutwhich the cable is trained to partially support the skip during part ofits movement, and said means being so located as to become ineffectiveafter a predetermined movement of the skip.

2. In combination with a loading skip adapted to be'raisedandlowered, apair of sheaves carried by the skip, a cable trained about said sheavesfor raising the skip, an auxiliary sheave intermediate said pair ofsheaves over which the cable passes, and flexible means for supportingthe 'auxiliary sheave `in the path of movement of the skip, wherebyV thelskip is partially supported by said auxiliary sheave and itssupport-ing.

means and the auxiliary sheave and its supporting.meansv becomesineffective aftery a predetermined movement of the skip.

3. In combination with a structure to be moved, a cable having itsmedial portion engaged with the structure at spaced points, means forapplying-tension to the cable ends to move the structure, a memberengaged with tliecable at a point intermediate said spaced points, andflexible means for holding the member in the path of travel of saidstructure to assist themeans for applyw ing tension to the cable endsinmoving the structure until the structure 'overtakes the member,continued movement of thestructure carryingl the member with it.

4. In combinationv with a loading skip adapted'tobe elevated from loadreceiving to charging: position, means for elevating the loading skipincluding a :cable having its medial portionc engaged with the'skip atspaced points, means forapplyingtension to the cable ends to elevate theskip, an i auxiliary support engaged `with the cable at apointintermediate its points of engagement with the .skip and iiexiblemeans-fon adapted to be-'lowered4 to and raised yfrom positionof maximumload, means for rais-v ing the skip includingza' cable connected withthe skip atspaced points thereon, an auxiliary cable'support with whichthe cable engages 'intermediate said points andP means normallysupporting the auxiliary, cable Cil support medially of the ends of thedistance of travel of the skip whereby the raising force applied by thecable is greatest during maximum load and whereby the speed of the skipaccelerates as it approches the auxiliary support.

6. ln combination with a loading skip adapted to be lowered to andelevated from a position or" maximum load, sheaves carried by the skip,an auxiliary sheave, means normally supporting the auxiliary sheave, acable trained about the sheaves for elevating the skip, the skip havinga predetermined distance oi'' travel, and the auxiliary sheave beinglocated medially of the ends of said distance of travel whereby theelevating i'orce applied by the cable is greatest during maximum loadand whereby the speed of the skip accelerates as it approaches theauxiliary sheave.

7. lin a loading skip adapted t-o be raised and lowered, sheaves carriedby the skip, an auxiliary sheave, means normally supporting theauxiliary sheave, a cable trained about the sheaves for raising theskip, the skip having a .predetermined distance of travel during raisingand lowering, and the auxiliary sheave being located medially of theends of said distance of travel and in a plane between the sheavescarried by the skip, whereby the raising force applied by the cable isgreatest at the initial raising of the skip and whereby the speed oi"the skip accelerates as it approaches the auxiliary slieave, saidauxiliary slieave moving with the skip throughout the remainder of thedistance of travel.

8. In a charging skip of the character dey scribed, a frame, ashaftmounted on said frame, a pair of spaced drums mounted on saidshaft, a pair of spaced sheaves mounted on said skip, a. hoisting cableattached at the ends thereof to said drums and trained around saidsheaves, a pair of iexible supporting members attached to said frame atspaced points and connected at the lower end of said members with theportion of said cable intermediate said sheaves and remote from the linejoining said sheaves when said skip is in lowered position.

9. ln a device to raise and lower material, a trame, a drum rotatablymounted on said trame, a cable attached at one end to said drum andengaging the device at spaced points intermediate the ends of saidcable, means flexibly supported from said frame engaeing said cableintermediate said spaced points and holding that portion of the cablebetween said spaced points above the lowermost position of said device.

l0. In a changing skip of the character described, a frame, a drumrotatably mounted on said frame, a pair of spaced sheaves mounted onsaid skip, a hoisting cable attached at one end thereof to said

